| 摘要 |
PURPOSE:The ester-interchange reaction between a flavonecarboxylic acid ester and an alcohol is effected using an orthotitanate as a catalyst to produce the titled compound with high conversion in high yield. CONSTITUTION:The ester-interchange reaction between a flavonecarboxylic acid ester of formula I (R<1> is alkyl, aralkyl; R<2>, R<3> are H, halogen; R<4> is H, aryl) such as methyl 3-methyl-flavone-8-carboxylate and an alcohol of the R<5>OH (R<5> is alkyl, aminoalkyl differing from R<1>) is carried out using an orthotitanate such as tetraethyl titanate as a catalyst usually in an inert solvent such as DMF at 50-200 deg.C, preferably for 3-12hr to give the objective compound of formula II. |
